It has been very well established that many diseases are spread by persons who share intravenous needles. Persons who share needles in this way are usually drug addicts and this brings about the spreading of such diseases as AIDS or hepatitis. It has been suggested, therefore, that the disease spread can be reduced by making clean needles available to drug users. However, there is no way of controlling the multiple use of needles when this is done. In addition, there is a rising concern among medical personnel who are involved in hypodermic needle use, either in connection with injection of medicines or in taking blood samples. A needle which has been used for this purpose, if contaminated with the disease, is a very dangerous instrumentality; there is documented evidence that nurses and doctors scratched by accident with such needles have had disease and even death from the contact. These problems have been obviated in a novel manner by the present invention.
It is therefore, an outstanding object of the present invention to provide a syringe that includes a mechanism that would allow a only one use of the syringe cylinder with any particular drug or fluid that is to be injected.
Another object of this invention is the provision of a hypodermic syringe having a mechanism that causes the plunger and needle assembly to become an integral assembly, thus preventing a second loading of the drug or fluid, because the mechanism stops the pump suction ability of the entire product.
A further object of the present invention is the provision of a hypodermic syringe that will assist in the national and international efforts to inhibit the spread of the AIDS virus among those intravenous drug users who now tend to share needles with fellow drug users.
It is another object of the present invention to provide a hypodermic needle that is capable of only one use, thus preventing the spread of any one of a number of diseases brought about by the sharing of contaminated needles.
A still further object of the invention is the provision of a syringe that, after a first use, causes the hypodermic needle to be retracted into the cylinder, thus providing for safer disposal and for relief of the significant level of fear among health care workers who must daily work with hypodermic syringes.
It is a further object of the invention to provide a hypodermic syringe which is simple in construction, which can be manufactured from relatively inexpensive materials, and which is capable of use and storage with a minimum of care.
With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.